Inspector Initials is the British Spy Union's equivalent of Major Monogram, and is the boss of Agent Double 0-0. She and Major Monogram seem to have a relationship together, or at least a mutual attraction ("Elementary My Dear Stacy").
- Inspector Initials bears a slight hair resemblance to Professor Poofenplotz, except her hair is not messed up, although this may just be a coincidence.
- Her character seems to be based on Judy Dench's incarnation of the James Bond character M.
- Like Major Monogram, Colonel Contraction, Admiral Acronym, and Director Dipthong, Inspector Initials' name consists of a rank over a linguistic term that begins with the same letter.
- "Elementary My Dear Stacy" (First appearance)